WO2020063817A1

WO2020063817A1 - Traffic lane line fitting method and system

Info

Publication number: WO2020063817A1
Application number: PCT/CN2019/108403
Authority: WO
Inventors: 甄龙豹; 葛建勇; 韩汝涛; 李龙; 李卫; 高健; 张凯; 和林; 张露
Original assignee: 长城汽车股份有限公司
Priority date: 2018-09-30
Filing date: 2019-09-27
Publication date: 2020-04-02
Also published as: KR102512207B1; CN110361021A; JP2022501612A; EP3859280A4; EP3859280A1; US20210389153A1; CN110361021B; US12007243B2; KR20210064369A; JP7185775B2

Abstract

A traffic lane line fitting method and system, the traffic lane line fitting method comprising: obtaining map information for a current position of a vehicle (S110), the map information comprising a number of traffic lanes, a road width and line point information of traffic lane lines on both sides of the vehicle; determining, from among the traffic lane lines on both sides of the vehicle, a traffic lane line on one side, consistent with the direction indicated by at least one of the following, to be a traffic lane line offset reference used for traffic lane line fitting (S120): a lane change direction side, a driving coordinate system reference side, a constant road width side, and a traffic lane continuous side; offsetting and generating a plurality of traffic lane lines of the vehicle on the basis of the traffic lane line offset reference (S130); performing curve fitting on a set of line points on the generated plurality of traffic lane lines so as to obtain a corresponding traffic lane line equation (S140). The traffic lane line fitting method solves the problem that extracted traffic lane lines are numerous and relatively complex.

Description

Lane line fitting method and system

Technical field

The present invention relates to the field of intelligent transportation, and in particular, to a lane line fitting method and system.

Background technique

At present, vehicles with Autonomous Driving System (ADS) have begun to be gradually introduced to the market, which has greatly promoted the development of intelligent transportation. ADS uses an environment awareness system installed on a vehicle to sense the surrounding environment in real time, and determines the driveable area of the vehicle through the data returned by the sensor. The content of environmental perception can be divided into two parts, road information and target information. The lane line information in the road information can provide the vehicle with travel path information, which is convenient for the realization of functions such as lateral control, lane change, and lane keeping. In addition, lane line information can also provide a baseline for screening targets in roads in an environmental awareness system.

Therefore, it can be known that lane line detection is important for ADS, and in order to ensure the driving safety of autonomous vehicles, the existing technology requires that the environment sensing system obtains as much lane line information as possible around the vehicle when sensing the surrounding environment. However, when there are changes such as bifurcations and intersections on the road, there may be multiple and relatively complicated lane lines directly output by the sensors, which cannot be directly used for decision-making and control of vehicle behavior.

Summary of the Invention

In view of this, the present invention aims to propose a lane line fitting method to solve the technical problem that there are multiple lane lines extracted in the prior art and that are relatively complicated.

To achieve the above object, the technical solution of the present invention is implemented as follows:

A lane line fitting method includes:

Obtain map information for the current position of the vehicle, where the map information includes the number of lanes, road width, and line point information of lane lines on both sides of the vehicle;

Determine the lane line on both sides of the vehicle that is consistent with the direction shown by at least one of the following as the lane line offset reference for lane line fitting; the lane change direction side indicates the expected of the vehicle on the current road Side of lane changing; reference side of driving coordinate system, wherein the driving coordinate system is based on the road boundary line on one side of the road where the vehicle is located, and the direction of the road guideline and the direction with the road guideline follow the left-hand rule The directions are two axes; the road width constant side indicates the side of the road ahead of which the vehicle does not change; the lane continuous side indicates the side of the current road where the lane continuity does not change; and

A plurality of lane lines of the own vehicle are generated based on the lane line offset reference offset, and a set of line points on the generated plurality of lane lines is subjected to curve fitting to obtain a corresponding lane line equation.

Further, the lane line fitting method further includes: acquiring a decision lane changing signal and / or navigation information for the current position of the own vehicle, wherein the decision lane changing signal indicates the lane changing direction side of the own vehicle, and The navigation information is used to indicate a constant width side of the road.

Further, the lane line fitting method further includes: determining to determine the lane line offset based on the lane changing direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side. The priority of the benchmark.

Further, the lane line fitting method further includes: determining an actual road working condition of the vehicle according to the map information, and selecting, based on the actual road working condition, a road width based on the lane changing direction side and the road width. One or more of the changing side, the lane continuous side, and the driving coordinate system reference side determine the lane line offset reference. Wherein, the actual road conditions and the lane line deviation reference selected by them include any one of the following: in the actual road conditions are a separate roadbed, a conventional ramp, a conventional main road, a ramp branching or driving In the case of a high-speed lane, selecting the lane line offset reference based on the lane change direction side and / or the driving coordinate system reference side; in the case where the actual road conditions narrow the main lane, Choose to determine the lane line offset reference based on the road width invariant side; and if the actual road conditions are ramp merge or ramp main road intersection, choose to be based on the lane continuous side and / or The reference side of the driving coordinate system is used to determine the lane line offset reference.

Further, the lane line fitting method further includes: in combination with the map information, completely or partially excluding lane lines outside the road boundary of the current road or affected by road obstacles from the plurality of lane lines.

Compared with the prior art, the lane line fitting method according to the present invention has the following advantages: The lane line fitting method according to the embodiment of the present invention can accurately and quickly determine a lane line offset reference for lane line fitting, and The effective lane line is output based on the lane line offset reference, which is helpful for lane keeping and other controls. It solves the problem of the large number of lane lines extracted in the current technology and is relatively complex. It can adapt to different road scenarios and the lane line algorithm handles High efficiency.

Another object of the present invention is to propose a lane line fitting system to solve the technical problem that there are multiple lane lines extracted in the prior art and that are relatively complicated.

A lane line fitting system includes:

An information obtaining unit, configured to obtain map information for the current position of the vehicle, wherein the map information includes the number of lanes, the road width, and line point information of the lane lines on both sides of the vehicle;

A reference determination unit, which is electrically connected to the information acquisition unit, and is configured to determine a lane line on one side of the vehicle lane that is consistent with a direction shown in at least one of the following lane lanes for lane line fitting Offset reference; side of the lane change direction, indicating the side of the current road where the vehicle is expected to change lanes; reference side of the driving coordinate system, where the driving coordinate system is based on the road boundary line on the side of the road where the vehicle is located, and is based on the road The direction of the guide line and the direction following the left-hand rule with the direction of the road guide line are two axes; the road width constant side indicates the side of the road ahead of the vehicle where the road width does not change; the continuous lane side indicates the current road The side of the middle lane where the continuity does not change;

A lane line fitting unit is electrically connected to the information acquisition unit and the reference determination unit, and is configured to generate a plurality of lane lines of the vehicle based on the lane line offset reference offset, and to generate a plurality of lane lines of the vehicle. The set of line points on the lane line is subjected to curve fitting to obtain the corresponding lane line equation.

Further, the information acquiring unit is further configured to acquire a decision-making lane changing signal and / or navigation information for the current position of the own vehicle, wherein the decision-making lane changing signal indicates the lane changing direction side of the own vehicle, and the navigation information It is used to indicate the constant width of the road.

Further, the lane line fitting system further includes: a priority setting unit for setting a side based on the lane changing direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side Determine the priority of the lane line offset reference; and the reference determining unit is further electrically connected to the priority setting unit and is configured to be based on the lane changing direction side set by the priority setting unit, The lane width invariant side, the lane continuous side, and the driving coordinate system reference side determine a priority of the lane line offset reference to determine the lane line offset reference.

Further, the lane line fitting system further includes: a road working condition determining unit, configured to determine an actual road working condition of the vehicle according to the map information; and the reference determination unit further determines with the road working condition The unit is electrically connected, and is used to select one based on the lane changing direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side according to the actual road conditions or Many determine the lane line offset reference. Wherein, the actual road conditions and the lane line deviation reference selected by them include any one of the following: in the actual road conditions are a separate roadbed, a conventional ramp, a conventional main road, a ramp branching or driving In the case of a high-speed lane, selecting the lane line offset reference based on the lane change direction side and / or the driving coordinate system reference side; in the case where the actual road conditions narrow the main lane, Choose to determine the lane line offset reference based on the road width invariant side; and if the actual road conditions are ramp merge or ramp main road intersection, choose to be based on the lane continuous side and / or The reference side of the driving coordinate system is used to determine the lane line offset reference.

Further, the lane line fitting system further includes: a lane line screening unit, which is electrically connected to the lane line fitting unit, and is configured to combine the map information to completely or partially from the plurality of lane lines. Remove lane lines that are outside the road boundary of the current road or affected by road obstacles.

The lane line fitting system has the same advantages as the above-mentioned lane line fitting method over the prior art, and is not repeated here.

Another object of the present invention is to provide a machine-readable storage medium having instructions stored on the machine-readable storage medium, which are used to cause a controller to execute the lane line fitting method described above.

Other features and advantages of the present invention will be described in detail in the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and the descriptions thereof are used to explain the present invention, and do not constitute an improper limitation on the present invention. In the drawings:

1 is a schematic flowchart of a lane line fitting method according to an embodiment of the present invention;

2 is a schematic diagram of a driving coordinate system X _F O _F Y _F and a global coordinate system X _G O _G Y _G and a vehicle coordinate system X _H O _H Y _H according to an embodiment of the present invention;

3 is a schematic diagram of an example of lane line fitting based on a lane change direction side in an embodiment of the present invention;

4 is a schematic diagram of an example of lane line fitting based on a reference side of a driving coordinate system in an embodiment of the present invention;

5 is a schematic diagram of an example of lane line fitting based on a road width constant side in an embodiment of the present invention;

6 is a schematic diagram of an example of lane line fitting based on a continuous side of a lane in an embodiment of the present invention;

FIG. 7 is an example of determining the priority of the lane line offset reference based on the lane changing direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side in the embodiment of the present invention. Example schematic of lane line fitting;

Fig. 8 (a) is a schematic diagram of lane line fitting of a separate roadbed, Fig. 8 (b) is a schematic diagram of lane line fitting of a conventional ramp, and Fig. 8 (c) is a schematic diagram of lane line fitting of a conventional main road, Fig. 8 ( d) is a schematic diagram of the lane line fitting of a ramp bifurcation, and FIG. 8 (e) is a schematic diagram of the lane line fitting of a departure highway lane;

FIG. 9 is a schematic diagram of lane line fitting with a narrowed main road; FIG.

FIG. 10 (a) is a schematic diagram of lane line fitting of a ramp merge, and FIG. 10 (b) is a schematic diagram of a lane line fitting of a main road intersection of the ramp;

FIG. 11 (a) is a schematic diagram of a lane line excluded from a road boundary of a current road, and FIG. 11 (b) is a schematic diagram of a lane line removed from a road obstacle; and

FIG. 12 is a schematic structural diagram of a lane line fitting system according to an embodiment of the present invention.

detailed description

It should be noted that, in the case of no conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

In the embodiment of the present invention, “electrical connection” is used to describe a signal connection between two components, such as a control signal and a feedback signal, and an electrical power connection between the two components. In addition, the "connection" involved in the embodiment of the present invention may be a wired connection or a wireless connection, and the "electrical connection" may be a direct electrical connection between two components, or may be through other components. Indirect electrical connection.

The present invention will be described in detail below with reference to the drawings and embodiments.

FIG. 1 is a schematic flowchart of a lane line fitting method according to an embodiment of the present invention. The lane line fitting method is used for an autonomous vehicle. As shown in FIG. 1, the lane line fitting method includes:

Step S110: Acquire map information for the current position of the vehicle.

The map information includes the number of lanes, road width, and line point information of lane lines on both sides of the vehicle. In a more preferred embodiment, the map information may further include a road type, a road feature point, a lane width, and the like. Among them, a road feature point is a point that can characterize a specific location of a road in a road scene, such as the start and end points of a road.

The map information is preferably high-precision map information. Those skilled in the art may know that the high-precision map information can show the above-mentioned road types, lane numbers, road widths, road feature points, and lines of lane lines on both sides of the vehicle. Point and lane width. Among them, the high-precision map divides the road into a set of map points, and the map output will divide the road from the location where the road changed, and will provide the relevant map information of the current road and the road at the same time.

In step S120, one lane line of the lane lines on both sides of the host vehicle is determined as a lane line offset reference for lane line fitting.

Specifically, in step S120, the lane line on one side of the lane line on both sides of the vehicle that is consistent with the direction shown by at least one of the following is used as a lane line offset reference for lane line fitting:

1) The lane change direction side indicates the side of the road where the vehicle is expected to change lanes.

The lane line fitting method according to the embodiment of the present invention may further include: obtaining a decision lane changing signal for the current position of the vehicle, wherein the decision lane changing signal indicates the lane changing direction side of the own vehicle.

Among them, the decision-making lane change signal can be given by a decision-making system of an autonomous vehicle. The decision-making system determines whether to change lanes according to the current vehicle data, road data, and target data, and gives a corresponding decision-making lane change signal, such as lane keeping. (Do not change lanes), change lanes on the left and change lanes incomplete, change lanes on the right and change lanes incomplete, change lane signals and change lanes complete, etc.

2) The reference side of the driving coordinate system.

The driving coordinate system is based on a road boundary line on one side of the road on which the vehicle is located, and the directions of the road guideline and the direction following the left-hand rule with the direction of the road guideline are two axes. 2 is a schematic diagram of a driving coordinate system X _F O _F Y _F and a global coordinate system X _G O _G Y _G and a vehicle coordinate system X _H O _H Y _H according to an embodiment of the present invention. As shown in Figure 2, the global coordinate system X _G O _G Y _G is based on the geodetic coordinate system, with X _G pointing north, Y _G pointing east, and the clockwise direction is positive, and the angle range is [0, 360 °]. Among them, the map lane line information is given based on the global coordinate system. The vehicle coordinate system X _H O _H Y _H is based on the own vehicle. X _H points to the longitudinal axis of the vehicle and Y _H points to the transverse axis of the vehicle. Following the right-hand rule, it is positive counterclockwise. The camera, lidar, The output information of the sensor of the millimeter wave radar is given based on the vehicle coordinate system. According to the definition of the global coordinate system and the vehicle coordinate system, the driving coordinate system of the embodiment of the present invention can be correspondingly represented as X _F O _F Y _F , which is a coordinate system established on the road boundary line and completely consistent with the road trend. After determining the origin O _F (X _Fo , Y _Fo ), the arc length distance between each point on the road boundary line and the driving coordinate origin O _F (X _Fo , Y _Fo ) can be calculated as the driving ordinate X _{Fi of} each point Therefore, the vertical axis X _{F of} the driving coordinate system is completely consistent with the road trend. The horizontal coordinate of the driving coordinate of each reference line point is Y _Fi = 0, and the vehicle position, lane line, and target can be based on the driving. The coordinate system is given, and especially in curve conditions, the real curve arc distance is used as the target distance information output. Compared with the lane coordinate system, it can avoid the target area attribute and the effective distance error. In addition, if points are used to describe each lane line in the driving coordinate system, it is easy to know that the horizontal coordinate of each point on the lane line in the driving coordinate system is the same, and only the vertical coordinate is different. For example, referring to FIG. 2, select On a fixed lane line, the ordinate increases in order, and the abscissa is 3.75. In this way, in the driving coordinate system, the lane line can be described using the ordinate of the lane line.

After the driving coordinate system has been established, the direction information of the reference side of the driving coordinate system can be obtained (the driving coordinate system is established on the left or right side of the road), and then the lane lines on both sides of the vehicle are output according to the high-precision map And determine the side that is consistent with the direction of the reference side of the driving coordinate system as the lane line offset reference.

In addition, the driving coordinate system reference side can be switched. For example, the switching rule is: using a preset default road boundary line as the reference line; switching to the navigation direction side road boundary line shown in the navigation direction information; If the road on which the vehicle is currently on is a ramp, the current reference line remains unchanged; if the road on which the vehicle is currently on is a main road, it is switched to the default road boundary line.

3) The road width constant side indicates the side where the road width does not change in the road ahead of the vehicle.

The lane line fitting method according to the embodiment of the present invention may further include: obtaining navigation information for the current position of the vehicle, where the navigation information is used to indicate the constant width of the road. Specifically, the navigation information is obtained, for example, by an in-vehicle navigation system with a GPS positioning function, which can indicate real-time road width changes (narrowing on the left, widening on the left, narrowing on the right, widening on the right, etc.) Then, according to the position points of the lane lines on both sides of the vehicle output from the high-precision map, and determine the side that is consistent with the direction of the road width constant side as the lane line offset reference.

4) Lane continuous side, which indicates the side where the lane continuity does not change in the current road.

For example, on a freeway, there is no change in the road width, but the number of lanes changes. There must be a situation where one side of the lane is continuous and the other side is discontinuous. Therefore, the lane line deviation can be determined according to the continuous side of the lane. Move the benchmark.

Step S130: Generate a plurality of lane lines of the host vehicle based on the lane line offset reference offset.

Preferably, step S130 may include the following steps: calculating a heading angle at each line point on the lane line offset reference; and based on the coordinates, the heading angle, and each line point on the lane line offset reference and The preset lane width is shifted left and / or right to the preset lane width to generate a plurality of lane lines of the vehicle. The calculation formula is explained as follows:

Original points: (x (1), x (2), x (3), ..., x (n); y (1), y (2), y (3), ..., y (n)) .

Calculate the heading angle information:

yaw (1) = atan2 ((y (1)), x (1))) * 180 / pi;

yaw (2) = atan2 ((y (2) -y (1)), (x (2) -x (1))) * 180 / pi;

yaw (3) = atan2 ((y (3) -y (2)), (x (3) -x (2))) * 180 / pi ;.

yaw (n) = atan2 ((y (n) -y (n-1)), (x (n) -x (n-1))) * 180 / pi;

The offset formula for the points on the lane line (offset to the right) is as follows:

X (i) = x (i) + LaneWidth_m * sin (yaw (i));

Y (i) = y (i) -LaneWidth_m * cos (yaw (i));

LaneWidth_m represents the lane width (generally the default lane width is 3.75m).

It should be noted that, in the embodiment of the present invention, the lane lines on both sides of the human vehicle refer to the left lane line and the right lane line adjacent to the own vehicle, and do not include the left and right lane lines and the right and right lane lines. The multiple lane lines described include lane lanes on both sides of the vehicle, left and right lane lanes, and right and left lane lanes to the left or right of both lanes.

Step S140: Perform curve fitting on the generated set of line points on the plurality of lane lines to obtain a corresponding lane line equation.

Preferably, the lane line equation after fitting is used due to errors caused by its own fitting, resulting in a large error in the fitted lane line, and the original high-precision map lane line information is also given in the form of continuous points, so During the intelligent lane line offset process, the operation is maintained in the form of points to ensure equidistant offset. Until the lane line information is finally given, the cubic equation operation is performed and given as the driving of the cubic equation parameters.

The following will comprehensively describe by using the lane line fitting method according to the embodiment of the present invention. In this example, the map information is based on a high-precision map as an example. For the convenience of description, the following descriptions are based on the lane changing direction side, Four lane line fitting examples of the driving coordinate system, the road width constant side, and the lane continuous side.

1. Lane line fitting based on the lane change direction side.

Fig. 3 is an example schematic diagram of lane line fitting based on a lane change direction side in the embodiment of the present invention. In this example, the lane line fitting rule in the lane change state is: according to the location points of the lane lines on both sides of the vehicle output from the high-precision map, select the high-resolution map point information on the lane change direction side (200m in front, high precision in the rear 80m). Map point position) is assigned to the corresponding side lane line. At this time, the vehicle is in the left lane change state, then the left position point of the high-precision map own vehicle is assigned to R2, and R1 is used as the lane line offset reference. The lane width information of the side lane and the lane width information of the current lane in the future 100m are subjected to position point offset processing to obtain L1 and L2, and then the points on the corresponding lane line are fitted three times to obtain the lane line equation. Here, because the high-precision map only outputs the current width of the current lane of the lane where the vehicle is located and the width information of the left and right lanes of the current position of the vehicle, the left and left lane width information cannot be obtained, so the offset is temporarily based on a fixed 3.75m .

2. Lane line fitting based on the reference side of the driving coordinate system.

4 is a schematic diagram of an example of lane line fitting based on a reference side of a driving coordinate system in an embodiment of the present invention. In this example, the lane line fitting rule under the driving coordinate system is: according to the established driving coordinate system, the direction information of the reference side of the driving coordinate system can be obtained (the driving coordinate system is established on the left side of the road or on the right side of the road). The position points of the lane lines on both sides of the vehicle output with high-precision maps. Select the high-precision map point information (200m forward and 80m rear high-resolution map point positions) on the reference side of the driving coordinate system to give the corresponding lane lines. At this time, the vehicle In the lane keeping state, the reference side of the driving coordinate system is on the right side of the road, then R1 is used as the lane line offset reference, and then the position point is based on the left and right lane width information of the current position and the lane width information of the next 100m of the current lane. The offset processing obtains other lane lines, and then the points on the corresponding lane lines are fitted three times to obtain the lane line equation.

Third, the lane line fitting based on the constant width of the road.

FIG. 5 is a schematic diagram of an example of lane line fitting based on a road width constant side in an embodiment of the present invention. In this example, the lane line fitting rule based on the constant width of the road is as follows: Because the navigation signal can indicate the change in the width of the road ahead (left side narrows, left side widens, right side narrows, and right side widens) ), According to the position points of the lane lines on both sides of the vehicle output from the high-precision map, select the high-precision map point information on the side with constant road width (high-precision map point positions of 200m in the front and 80m in the rear) to give the corresponding side lane lines, such as As shown in Figure 5, the left side of the road ahead becomes narrower, then the high-precision map own vehicle's right position point is assigned to R1 as the lane line offset reference, and then based on the left and right lane width information and The lane width information at the current 100m of the current lane is subjected to position point offset processing to obtain other lane lines, and then the points on the corresponding lane lines are fitted three times to obtain the lane line equation.

Fourth, the lane line fitting based on the continuous side of the lane.

6 is a schematic diagram of an example of lane line fitting based on a continuous side of a lane in an embodiment of the present invention. In this example, the lane line fitting rule based on the continuous side of the lane is: Because there is no change in the width of the road on the highway, but the number of lanes changes, there must be a situation in which one lane is continuous and the other is discontinuous. Then, according to the position points of the lane lines on both sides of the vehicle output from the high-precision map, select the high-precision map point information on the continuous side of the lane (the high-precision map point positions of 200m in the front and 80m in the rear) to give the corresponding side lane lines, as shown in the figure. At this time, the vehicle is in the lane keeping state, and the right lane is continuous. Then the high-resolution map of the right side of the vehicle is assigned R1 as the lane line offset reference, and then the left and right lane width information and The lane width information at the current 100m of the current lane is subjected to position point offset processing to obtain other lane lines, and then the points on the corresponding lane lines are fitted three times to obtain the lane line equation.

Here, some operating conditions may be applicable to many of the lane line fitting schemes described above based on the lane change direction side, the driving coordinate system reference side, the road width constant side, and the lane continuous side. To avoid repeatedly performing lane line fitting, in a preferred embodiment, the lane line fitting method according to the embodiment of the present invention may further include: setting a side based on the lane changing direction side, the road width constant side, and the lane The continuous side and the driving coordinate system reference side determine the priority of the lane line offset reference.

FIG. 7 is an example of determining the priority of the lane line offset reference based on the lane changing direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side in the embodiment of the present invention. Example schematic of lane line fitting. In this example, the order of the priorities from high to low is: the lane changing direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side. As shown in FIG. 7, it may include the following steps:

In step S701, it is determined whether there is a lane change decision signal, and if there is, a lane line fitting based on the lane change direction side is performed, otherwise step S702 is performed.

In step S702, it is determined whether a road is narrowed or widened, and if there is, a lane line fitting is performed with the road width constant side as a reference, otherwise step S703 is performed.

Among them, when performing lane line fitting with the road width constant side as a reference, the actual road conditions need to be combined, such as whether the road is wider or narrower, whether to pass the road widening end point, and the left or right side is widened. Or narrow down to specifically determine the lane line offset reference, and then fit the lane line. For example, when the road is narrowing, if the left side is narrowing, the right lane line is used as the lane line offset reference to offset other lane lines, and if the right side is narrowing, the left lane line is used as the lane line offset reference. Offset other lane lines, among which it can also be judged whether the road width at 100m in the future is less than the set threshold, and if it is, it can give a status signal to the decision-making system of the autonomous driving vehicle at the same time. As another example, when the road is widened, it is determined whether to pass the road widening end point. If so, the left side is widened, and the right lane line is used as the lane line offset reference to offset other lane lines. The line is the lane line offset reference offset from other lane lines. If the road widening end point is not passed, the left side becomes wider and the right lane line is used as the lane line offset reference. The original road width is offset from the other lane lines and the right side becomes Width Use the left lane line as the lane line offset reference to offset the original road width to get other lane lines.

In step S703, it is determined whether the number of lanes of the current road and the lower road is changed. If yes, the lane line fitting based on the continuous side of the lane is performed, otherwise step S704 is performed.

When performing lane line fitting with the lane continuous side as a reference, if the number of lanes on both sides is continuous, step S704 is directly performed.

Step S704: Perform lane line fitting based on the reference side of the driving coordinate system.

Further, the above-mentioned four lane line fitting schemes based on the lane changing direction side, the driving coordinate system reference side, the road width constant side, and the lane continuous side can be applied to various road conditions. In a preferred embodiment, the lane line fitting method further includes: determining an actual road condition of the vehicle according to the map information, and selecting, based on the actual road condition, selection One or more of the road width invariant side, the lane continuous side, and the driving coordinate system reference side determine the lane line offset reference.

For example, the actual road conditions and the lane line offset reference selected by the road conditions may include any of the following:

1) In the case where the actual road conditions are a separate subgrade, a conventional ramp, a conventional main road, an on-ramp bifurcation, or driving off a high-speed lane, the selection is based on the lane change direction side and / or the driving coordinate system reference Side to determine the lane line offset reference.

Among them, FIG. 8 (a) is a schematic diagram of lane line fitting of a separate roadbed, FIG. 8 (b) is a schematic diagram of lane line fitting of a conventional ramp, and FIG. 8 (c) is a schematic diagram of lane line fitting of a conventional main road. 8 (d) is a schematic diagram of a lane line fitting for a bifurcation of a ramp, and FIG. 8 (e) is a schematic diagram of a lane line fitting for a departure from a high-speed lane. As shown in Fig. 8 (a)-Fig. 8 (c), the lane line L1 on the side where the driving coordinate system is located is selected as the lane line offset reference to offset to obtain other lane lines, and a lane change signal is received, for example, Changing lanes to the left also uses lane line L1 as the lane line offset reference to offset to obtain other lane lines. As shown in Fig. 8 (d) and Fig. 8 (e), the lane line R1 on the side where the driving coordinate system is located is selected as the lane line offset reference to offset to obtain other lane lines, and the received vehicle can only change to the right For lanes, the lane line R1 is used as the lane line deviation reference to obtain other lane lines.

2) In the case where the actual road conditions are narrowed as the main road, selecting the lane line offset reference based on the road width invariant side is selected.

Among them, FIG. 9 is a schematic diagram of lane line fitting with a narrowed main road. As shown in FIG. 9, the navigation information indicates that the right side of the main lane becomes narrower and the width on the left side remains unchanged. The left lane line L1 is used as the lane line offset reference to obtain other lane lines.

3) In a case where the actual road condition is a ramp merge or a ramp main road intersection, the lane line offset reference is selected to be determined based on the lane continuous side and / or the driving coordinate system reference side.

Among them, FIG. 10 (a) is a schematic diagram of lane line fitting for merged ramps, and FIG. 10 (b) is a schematic diagram of lane line fitting for intersections of main ramps. As shown in Figure 10 (a), one lane line R1 in the direction of the driving coordinate system is selected as the lane line deviation reference to obtain other lane lines, and the number of lanes on the left side of the vehicle is not continuous under this road condition ( There is a change in the number of lanes), so the lane lanes with continuous lane lanes R1 should be used as the lane line deviation reference to obtain other lane lanes. As shown in Figure 10 (b), first select the lane line R1 in the direction of the driving coordinate system as the lane line offset reference to offset the other lane lines. After passing the acceleration lane starting point, the driving coordinate system should be switched to the road On the far left, the left lane line L1 is used as the lane line offset reference to offset to obtain other lane lines. In addition, under the road conditions shown in FIG. 10 (b), the number of lanes on the left side of the vehicle is discontinuous (the number of lanes changes) before passing the starting point of the acceleration lane. Therefore, the lane lane continuous R1 should be used as the lane line. The offset reference is used to obtain other lane lines by offset, and the number of lanes on the right is discontinuous (the number of lanes varies) before passing the starting point of the accelerating lane. Therefore, the left lane line L1 with continuous lanes should be used as the lane offset reference. Offset to get other lane lines.

Furthermore, the above lane line fitting example is based on the four lane lines L1, L2, R1, and R2 for fitting and output, but some lane lines, such as L2 or R2, may already be outside the road boundary. Cooperation is invalid. Therefore, the lane line fitting method in the embodiment of the present invention may further include: in combination with the map information, excluding all or part of the plurality of lane lines outside a road boundary of a current road or affected by road obstacles. Lane lines. Among them, FIG. 11 (a) is a schematic diagram of excluding lane lines outside the road boundary of the current road. It can be seen that the fitted L2 does not actually exist, and it should be considered to delete L2. Figure 11 (b) is a schematic diagram of the lane line affected by road obstacles. It can be seen that the fitted L2 part is affected by the obstacle. The lane formed by L2 and L1 is not actually passing through, so that The fitted part L2 is not consistent with the actual road plan, and it should be considered to delete the unreasonable fitting in L2.

In summary, the lane line fitting method according to the embodiment of the present invention can accurately and quickly determine a lane line offset reference for lane line fitting, and output a valid lane line based on the lane line offset reference, which is beneficial to the lane Maintaining other controls solves the problem of the large and relatively complicated number of lane lines extracted in the current technology, which can be adapted to different road scenes, and the lane line algorithm processing efficiency is high.

FIG. 12 is a schematic structural diagram of a lane line fitting system according to an embodiment of the present invention. The lane line fitting system and the above embodiment of the lane line fitting method are based on the same inventive idea. As shown in FIG. 12, the lane line fitting system may include:

The information acquisition unit 1 is configured to acquire map information for the current position of the vehicle, where the map information includes the number of lanes, the road width, and line point information of the lane lines on both sides of the vehicle.

The reference determination unit 2 is electrically connected to the information acquisition unit 1 and is used to determine that a lane line on one side of the vehicle lane that is consistent with a direction shown by at least one of the following is used for lane line fitting. Lane line offset reference; lane change direction side, indicating the side of the current road where the vehicle is expected to change lanes; driving coordinate system reference side, where the driving coordinate system is based on the road boundary line on the side of the road where the vehicle is located, The direction of the road guideline and the direction following the left-hand rule with the direction of the road guideline are two axes; the road width constant side indicates the side of the road ahead of the vehicle where the road width does not change; the lane continuous side indicates The side of the current road where lane continuity does not change.

The lane line fitting unit 3 is electrically connected to the information acquisition unit 1 and the reference determination unit 2 and is configured to generate a plurality of lane lines of the vehicle based on the lane line offset reference offset, and A set of line points on a plurality of lane lines is subjected to curve fitting to obtain corresponding lane line equations.

In a preferred embodiment, the information acquisition unit 1 is further configured to obtain a decision-making lane change signal and / or navigation information for the current position of the host vehicle, wherein the decision-making lane change signal indicates the lane change direction side of the host vehicle , The navigation information is used to indicate a constant width side of the road.

In a preferred embodiment, the lane line fitting system further includes: a priority setting unit 4 configured to set a side based on the lane changing direction side, the road width constant side, the lane continuous side, and the The reference side of the driving coordinate system determines the priority of the lane line offset reference; and the reference determination unit 2 is also electrically connected to the priority setting unit 4 and is configured to be based on the setting by the priority setting unit. The lane change direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side determine the priority of the lane line offset reference to determine the lane line offset reference.

In a more preferred embodiment, the lane line fitting system further includes: a road condition determining unit 5 for determining an actual road condition of the vehicle according to the map information;

In addition, the reference determining unit 2 is also electrically connected to the road working condition determining unit 5 and is configured to select, based on the actual road working condition, the side based on the lane changing direction side, the road width constant side, and the lane. One or more of a continuous side and the driving coordinate system reference side determine the lane line offset reference.

Wherein, the actual road working conditions and the lane line deviation reference selected by them include any of the following: in a case where the actual road working conditions are a separate roadbed, a conventional ramp, a conventional main road or a ramp branching , Determining to determine the lane line offset reference based on the lane change direction side and / or the driving coordinate system reference side; when the actual road conditions narrow the main lane or drive away from a high-speed lane, Choose to determine the lane line offset reference based on the road width invariant side; and if the actual road conditions are ramp merge or ramp main road intersection, choose to be based on the lane continuous side and / or The reference side of the driving coordinate system is used to determine the lane line offset reference.

In a more preferred embodiment, the lane line fitting system further includes: a lane line screening unit 6, which is electrically connected to the lane line fitting unit 3, and is configured to combine the map information from the multiple Lane lanes are excluded in whole or in part from lane boundaries outside the current road or affected by road obstacles.

It should be noted that, for other implementation details and effects of the lane line fitting system according to the embodiment of the present invention, reference may be made to the foregoing embodiment of the lane line fitting method, and details are not described herein again.

The above description is only the preferred embodiments of the present invention, and is not intended to limit the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention, such as the execution of adaptive change steps The sequence and the connection relationship between the adjustment function modules should be included in the protection scope of the present invention.

Those skilled in the art can understand that all or part of the steps in the method of the above embodiment can be completed by a program instructing related hardware. The program is stored in a storage medium and includes several instructions to make a single chip, chip or processor (processor) executes all or part of the steps of the method described in each embodiment of the present application. The foregoing storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disks or optical disks and other media that can store program codes .

In addition, various combinations of the embodiments of the present invention can also be arbitrarily combined, as long as it does not violate the idea of the embodiments of the present invention, it should also be regarded as the content disclosed in the embodiments of the present invention.

Claims

A lane line fitting method is characterized in that the lane line fitting method includes:

Obtain map information for the current position of the vehicle, where the map information includes the number of lanes, road width, and line point information of lane lines on both sides of the vehicle;

Determine the lane line on one side of the vehicle that is consistent with the direction shown by at least one of the following as the lane line offset reference for lane line fitting:

The lane change direction side indicates the side of the road where the vehicle is expected to change lanes;

The reference side of the driving coordinate system, wherein the driving coordinate system is based on a road boundary line on one side of the road on which the vehicle is located, and the directions of the road guideline and the direction following the left-hand rule with the direction of the road guideline are two axes;

The road width constant side indicates the side of the road ahead of the vehicle where the road width does not change;

Lane Continuity Side, which indicates the side where lane continuity does not change on the current road;

A plurality of lane lines of the own vehicle are generated based on the lane line offset reference offset, and a set of line points on the generated plurality of lane lines is subjected to curve fitting to obtain a corresponding lane line equation.
The lane line fitting method according to claim 1, wherein the lane line fitting method further comprises:

A decision-making lane change signal and / or navigation information for the current position of the own vehicle is obtained, where the decision-change lane signal indicates the side of the lane change direction of the own vehicle, and the navigation information is used to indicate the road width constant side.
The lane line fitting method according to claim 1, wherein the lane line fitting method further comprises:

Setting a priority for determining the lane line offset reference based on the lane changing direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side.
The lane line fitting method according to claim 1, wherein the lane line fitting method further comprises:

Determine the actual road conditions of the vehicle according to the map information, and select based on the lane change direction side, the road width constant side, the lane continuous side, and the driving coordinates according to the actual road conditions One or more of the reference sides determine the lane line offset reference.
The lane line fitting method according to claim 4, wherein the actual road conditions and the lane reference offset selected by the lane line include any one of the following:

In the case that the actual road conditions are a separate subgrade, a conventional ramp, a conventional main road, an on-ramp bifurcation, or a departure from a high-speed lane, selecting based on the lane change direction side and / or the driving coordinate system reference side Determining the lane line offset reference;

In a case where the actual road conditions are narrowed for the main lane, selecting the lane line offset reference based on the constant width side of the road; and

In a case where the actual road condition is a ramp merge or a ramp main road intersection, the lane line offset reference is selected to be determined based on the lane continuous side and / or the driving coordinate system reference side.
The lane line fitting method according to any one of claims 1 to 5, wherein the lane line fitting method further comprises:

In combination with the map information, lane lines that are outside the road boundary of the current road or affected by road obstacles are completely or partially excluded from the plurality of lane lines.
A machine-readable storage medium stores instructions on the machine-readable storage medium, which are used to cause a controller to execute the lane line fitting method according to any one of claims 1 to 6.
A lane line fitting system is characterized in that the lane line fitting system includes:

An information obtaining unit, configured to obtain map information for the current position of the vehicle, wherein the map information includes the number of lanes, the road width, and line point information of the lane lines on both sides of the vehicle;

A reference determination unit, which is electrically connected to the information acquisition unit, and is configured to determine a lane line on one side of the vehicle lane that is consistent with a direction shown in at least one of the following lane lanes for lane line fitting Offset reference; side of the lane change direction, indicating the side of the current road where the vehicle is expected to change lanes; reference side of the driving coordinate system, where the driving coordinate system is based on the road boundary line on the side of the road where the vehicle is located The direction of the guide line and the direction following the left-hand rule with the direction of the road guide line are two axes; the road width constant side indicates the side of the road ahead of the vehicle where the road width does not change; the continuous lane side indicates the current road The side of the middle lane where the continuity does not change;

A lane line fitting unit is electrically connected to the information acquisition unit and the reference determination unit, and is configured to generate a plurality of lane lines of the vehicle based on the lane line offset reference offset, and to generate a plurality of lane lines of the vehicle. The set of line points on the lane line is subjected to curve fitting to obtain the corresponding lane line equation.
The lane line fitting system according to claim 8, wherein the information acquisition unit is further configured to obtain a decision lane change signal and / or navigation information for the current position of the vehicle, wherein the decision lane change signal indicates On the side of the lane changing direction of the own vehicle, the navigation information is used to indicate that the road width does not change.
The lane line fitting system according to claim 8, wherein the lane line fitting system further comprises:

A priority setting unit configured to set a priority for determining the lane line offset reference based on the lane change direction side, the road width constant side, the lane continuous side, and the driving coordinate system reference side;

In addition, the reference determination unit is also electrically connected to the priority setting unit, and is configured to be based on the lane changing direction side, the road width constant side, and the lanes being continuous set by the priority setting unit. The side and the driving coordinate system reference side determine the priority of the lane line offset reference to determine the lane line offset reference.
The lane line fitting system according to claim 8, wherein the lane line fitting system further comprises:

A road condition determining unit, configured to determine an actual road condition of the vehicle according to the map information;

In addition, the reference determination unit is also electrically connected to the road condition determination unit, and is configured to select, based on the actual road condition, based on the lane change direction side, the road width constant side, and the lane. One or more of a continuous side and the driving coordinate system reference side determine the lane line offset reference.
The lane line fitting system according to claim 11, wherein the actual road conditions and the lane reference offset selected by the lane line include any one of the following:

In the case that the actual road conditions are a separate subgrade, a conventional ramp, a conventional main road, an on-ramp bifurcation, or a departure from a high-speed lane, selecting based on the lane change direction side and / or the driving coordinate system reference side Determining the lane line offset reference;

In a case where the actual road conditions are narrowed for the main lane, selecting the lane line offset reference based on the constant width side of the road; and

In a case where the actual road condition is a ramp merge or a ramp main road intersection, the lane line offset reference is selected to be determined based on the lane continuous side and / or the driving coordinate system reference side.
The lane line fitting system according to any one of claims 8 to 12, wherein the lane line fitting system further comprises:

The lane line screening unit is electrically connected to the lane line fitting unit, and is used to combine the map information to completely or partially remove from the plurality of lane lines outside the road boundary of the current road or affected by road obstacles. Affected lane lines.